/**
 *    Copyright 2009-2020 the original author or authors.
 *
 *    Licensed under the Apache License, Version 2.0 (the "License");
 *    you may not use this file except in compliance with the License.
 *    You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 */
package org.apache.ibatis.aapl.script.creator;

import org.apache.ibatis.aapl.annotation.TableWatcher;
import org.apache.ibatis.aapl.util.*;

import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.List;

public class SelectSqlCreator implements SqlCreator {
  @Override
  public String createSql(String script, Method method, TableWatcher watcher) {

    Class<?> returnType = ReflectUtil.getMethodReturnType(method);
    Clause clause = ClauseUtil.parse(script);

    StringBuilder builder = new StringBuilder();
    builder.append("select ");

    Field[] fields = returnType.getDeclaredFields();
    List<String> fieldsList = new ArrayList<>();

    List<String> excepts = clause.except();
    for (Field field : fields) {
      boolean flg = Modifier.isStatic(field.getModifiers());
      if (flg) {
        continue;
      }
      String name = field.getName();
      if (excepts.contains(name)) {
        continue;
      }
      name = NameUtil.camel2Underline(name);
      fieldsList.add(name);
    }

    for (int i = 0; i < fieldsList.size(); i++) {
      builder.append(fieldsList.get(i));
      if (i != fieldsList.size() - 1) {
        builder.append(",");
      }
    }

    builder.append(" from ");
    builder.append(watcher.value());
    if (clause.where() != null) {
      builder.append(" ");
      builder.append(clause.where());
    }
    if (clause.orderBy() != null) {
      builder.append(" ");
      builder.append(clause.orderBy());
    }
    builder.append(" limit #{limit} offset #{offset} ");
    return builder.toString();
  }
}
